The slavery extension question had seemingly been settled by the Missouri Compromise nearly 40 years earlier. The Mexican War, however, had added new territories, and the issue flared up again in the 1840s. The Compromise of 1850 provided a temporary respite from sectional strife, but the Kansas-Nebraska Act of 1854—a measure Douglas sponsored—brought the slavery extension issue to the fore once again. Douglas’s bill in effect repealed the Missouri Compromise by lifting the ban against slavery in territories north of the 36°30′ latitude. In place of the ban, Douglas offered popular sovereignty, the doctrine that the actual settlers in the territories and not Congress should decide the fate of slavery in their midst.

Stephen A. Douglas.

Library of Congress, Washington, D.C.

The Kansas-Nebraska Act spurred the creation of the Republican Party, formed largely to keep slavery out of the western territories. Both Douglas’s doctrine of popular sovereignty and the Republican stand on free soil were seemingly invalidated by the Dred Scott decision of 1857, in which the Supreme Court said that neither Congress nor the territorial legislature could exclude slavery from a territory.

When Lincoln and Douglas debated the slavery extension issue in 1858, therefore, they were addressing the problem that had divided the nation into two hostile camps and that threatened the continued existence of the Union. Their contest, as a consequence, had repercussions far beyond determining who would win the senatorial seat at stake.

When Lincoln received the Republican nomination to run against Douglas, he said in his acceptance speech that “A house divided against itself cannot stand” and that “this government cannot endure permanently half slave and half free.” Douglas thereupon attacked Lincoln as a radical, threatening the continued stability of the Union. Lincoln then challenged Douglas to a series of debates, and the two eventually agreed to hold joint encounters in seven Illinois congressional districts.

Abraham Lincoln, from a photograph made at Beardstown, Illinois, during the 1858 debates.

The debates, each three hours long, were convened in Ottawa (August 21), Freeport (August 27), Jonesboro (September 15), Charleston (September 18), Galesburg (October 7), Quincy (October 13), and Alton (October 15). Douglas repeatedly tried to brand Lincoln as a dangerous radical who advocated racial equality and disruption of the Union. Lincoln emphasized the moraliniquity of slavery and attacked popular sovereignty for the bloody results it had produced in Kansas.

Life-size bronze statues of Stephen A. Douglas (left) and Abraham Lincoln at the site of their 1858 …

At Freeport Lincoln challenged Douglas to reconcile popular sovereignty with the Dred Scott decision. Douglas replied that settlers could circumvent the decision by not establishing the local police regulations—i.e., a slave code—that protected a master’s property. Without such protection, no one would bring slaves into a territory. This became known as the “Freeport Doctrine.”

Douglas’s position, while acceptable to many Northern Democrats, angered the South and led to the division of the last remaining national political institution, the Democratic Party. Although he retained his seat in the Senate, narrowly defeating Lincoln when the state legislature (which then elected U.S. senators) voted 54 to 46 in his favour, Douglas’s stature as a national leader of the Democratic Party was gravely diminished. Lincoln, on the other hand, lost the election but won acclaim as an eloquent spokesman for the Republican cause.

In 1860 the Lincoln-Douglas debates were printed as a book and used as an important campaign document in the presidential contest that year, which once again pitted Republican Lincoln against Democrat Douglas. This time, however, Douglas was running as the candidate of a divided party and finished a distant second in the popular vote to the triumphant Lincoln.

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Lincoln challenged the incumbent Douglas for the Senate seat in 1858, and the series of debates they engaged in throughout Illinois was political oratory of the highest order. Both men were shrewd debaters and accomplished stump speakers, though they could hardly have been more different in style and appearance—the short and pudgy Douglas, whose stentorian voice and graceful gestures...

On August 27, 1858, Freeport was the site of the second Lincoln-Douglas debate, during which Stephen A. Douglas formulated the “Freeport Doctrine,” in which he argued that a territory had the right to exclude slavery despite contrary U.S. Supreme Court decisions. Lincoln the Debater, a statue by Leonard Crunelle in Taylor Park, commemorates the debate and...

...granted to Knox Manual Labor College (renamed Knox College in 1857); in 1930 it absorbed Lombard College, which had been founded by Universalists in 1851. The Knox campus was the site of the fifth Lincoln-Douglas debate on the slavery issue in 1858.

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In the 1858 election for U.S. senator from the state of Illinois, the candidates were Abraham Lincoln and Stephen A. Douglas. They met seven times to debate, or discuss, important topics. The main topic was whether slavery should be allowed in new states forming to the West.